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#include "libgcc.h"
; numerator in A0/A1
; denominator in A2/A3
.global __modsi3
__modsi3:
PUSHP S2P
bsr modnorm
bsr __divsi3
mov.l er3,er0
bra exitdiv
.global __umodsi3
__umodsi3:
bsr __udivsi3
mov.l er3,er0
rts
.global __divsi3
__divsi3:
PUSHP S2P
jsr divnorm
bsr __udivsi3
; examine what the sign should be
exitdiv:
btst #3,S2L
beq reti
; should be -ve
neg.l A0P
reti:
POPP S2P
rts
divnorm:
mov.l A0P,A0P ; is the numerator -ve
stc ccr,S2L ; keep the sign in bit 3 of S2L
bge postive
neg.l A0P ; negate arg
postive:
mov.l A1P,A1P ; is the denominator -ve
bge postive2
neg.l A1P ; negate arg
xor.b #0x08,S2L ; toggle the result sign
postive2:
rts
;; Basically the same, except that the sign of the divisor determines
;; the sign.
modnorm:
mov.l A0P,A0P ; is the numerator -ve
stc ccr,S2L ; keep the sign in bit 3 of S2L
bge mpostive
neg.l A0P ; negate arg
mpostive:
mov.l A1P,A1P ; is the denominator -ve
bge mpostive2
neg.l A1P ; negate arg
mpostive2:
rts
.end
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